Also called Scheuermann’s disease, juvenile kyphosis, and vertebral epiphysitis, adolescent kyphosis is the most common form of this disorder. It may result from growth retardation or a vascular disturbance in the vertebral epiphysis (usually at the thoracic level) during periods of rapid growth or from congenital deficiency in the thickness of the vertebral plates.

Other causes include infection, inflammation, aseptic necrosis, and disk degeneration. The subsequent stress of weight bearing on the compromised vertebrae may result in the thoracic hump commonly seen in adolescents with kyphosis. Symptomatic adolescent kyphosis is more prevalent in girls than in boys and usually occurs between ages 12 and 16.

Also known as adult roundback, adult kyphosis may result from degeneration of intervertebral disks, atrophy, or osteoporotic collapse of the vertebrae that’s associated with aging; from an endocrine disorder, such as hyperparathyroidism or Cushing’s disease; or from prolonged steroid therapy.

Adult kyphosis may also result from conditions such as arthritis, Paget’s disease, polio, compression fracture of the thoracic vertebrae, metastatic tumor, plasma cell myeloma, or tuberculosis.
In children and adults, kyphosis may also result from poor posture.

Disk lesions called Schmorl’s nodes may develop in anteroposterior curving of the spine and are localized protrusions of nuclear material through the cartilage plates and into the spongy bone of the vertebral bodies. If the anterior portions of the cartilage are destroyed, bridges of new bone may transverse the intervertebral space, causing ankylosis.